com.numdata.printer.LPDClient Maven / Gradle / Ivy
/*
* Copyright (c) 2017, Numdata BV, The Netherlands.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of Numdata nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL NUMDATA BV BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package com.numdata.printer;
import java.awt.print.*;
import java.io.*;
import java.net.*;
import com.numdata.oss.*;
/**
* Client for the Line Printer Daemon Protocol.
*
* @author Gerrit Meinders
* @see RFC 1179: Line Printer
* Daemon Protocol
*/
public class LPDClient
{
/**
* The default LPD port number.
*/
public static final int DEFAULT_PORT = 515;
/**
* Host name of the printer.
*/
private final String _hostname;
/**
* Network port used by the LPD service.
*/
private final int _networkPort;
/**
* Queue name to be used.
*/
private final String _queueName;
/**
* Username to provide to the printer.
*/
private final String _userName;
/**
* Constructs a new instance.
*
* @param printerSettings Printer settings to use.
*/
public LPDClient( final PrinterSettings printerSettings )
{
this( printerSettings.getHostname(), printerSettings.getNetworkPort(), printerSettings.getQueueName() );
}
/**
* Constructs a new instance.
*
* @param hostname Host name or IP address of server.
* @param networkPort Port to use on host (0 or less to use default).
* @param queueName Name of remote printer queue or port.
*/
public LPDClient( final String hostname, final int networkPort, final String queueName )
{
_hostname = hostname;
_networkPort = ( networkPort <= 0 ) ? DEFAULT_PORT : networkPort;
_queueName = queueName;
_userName = "Unknown";
}
/**
* Requests information about the printer queue.
*
* @param longFormat {@code false} for short format; {@code true} for long
* format.
*
* @return Printer queue information.
*
* @throws PrinterException if an error occurs while accessing the printer.
*/
public String requestQueueState( final boolean longFormat )
throws PrinterException
{
try
{
final Socket socket = connect();
try
{
socket.setSoTimeout( 30000 );
final InputStream in = socket.getInputStream();
final OutputStream out = socket.getOutputStream();
final Writer writer = new OutputStreamWriter( out, "US-ASCII" );
writer.write( longFormat ? 0x04 : 0x03 );
writer.write( _queueName );
writer.write( '\n' );
writer.flush();
return TextTools.loadText( in );
}
finally
{
try
{
socket.close();
}
catch ( final IOException ignored )
{
}
}
}
catch ( final IOException e )
{
throw new PrinterIOException( e );
}
}
/**
* Removes the currently active job.
*
* @throws PrinterException if an error occurs while accessing the printer.
*/
public void removeCurrentJob()
throws PrinterException
{
try
{
final Socket socket = connect();
try
{
socket.setSoTimeout( 30000 );
final InputStream in = socket.getInputStream();
final OutputStream out = socket.getOutputStream();
final Writer writer = new OutputStreamWriter( out, "US-ASCII" );
writer.write( 0x05 );
writer.write( _queueName );
writer.write( ' ' );
writer.write( _userName );
writer.write( '\n' );
writer.flush();
if ( in.read() != 0 )
{
throw new PrinterException( "LPD print server '" + _hostname + "' refused to remove jobs." );
}
}
finally
{
try
{
socket.close();
}
catch ( final IOException ignored )
{
}
}
}
catch ( final IOException e )
{
throw new PrinterIOException( e );
}
}
/**
* Print a document to a LPD print server on a network host.
*
* This implementation conforms to RFC1179, except for the fact that it does
* not use local port numbers 721 - 731, which may not always be available.
*
* @param documentName Name of document to display in queue.
* @param documentData Document data to print.
* @param printRaw Print raw vs. cooked data.
*
* @throws PrinterException if there was a problem sending the document to
* the printer.
*/
public void print( final String documentName, final byte[] documentData, final boolean printRaw )
throws PrinterException
{
System.out.println( "LPD.print( " + documentName + ", " + documentData.length + " bytes of data, " + printRaw + " )" );
try
{
final Socket socket = connect();
try
{
final String jobNumber = "001"; // 001 to 999 (should cycle?)
socket.setSoTimeout( 30000 );
final String localHostName = "localhost";
final InputStream in = socket.getInputStream();
final OutputStream out = socket.getOutputStream();
final Writer writer = new OutputStreamWriter( out, "US-ASCII" );
final String hostname = _hostname;
// Open printer
writer.write( 0x02 );
writer.write( _queueName );
writer.write( (int)'\n' );
writer.flush();
if ( in.read() != 0 )
{
throw new FatalPrinterException( "LPD print server '" + hostname + "' did not recognize printer queue name '" + _queueName + '\'' );
}
// Send control file
final StringBuilder controlFile = new StringBuilder( 80 );
controlFile.append( 'H' );
controlFile.append( localHostName );
controlFile.append( '\n' );
controlFile.append( 'P' );
controlFile.append( _userName );
controlFile.append( '\n' );
controlFile.append( printRaw ? "o" : "p" );
controlFile.append( "dfA" );
controlFile.append( jobNumber );
controlFile.append( localHostName );
controlFile.append( '\n' );
controlFile.append( "UdfA" );
controlFile.append( jobNumber );
controlFile.append( localHostName );
controlFile.append( '\n' );
controlFile.append( 'N' );
controlFile.append( documentName );
controlFile.append( '\n' );
writer.write( 0x02 );
writer.write( String.valueOf( controlFile.length() ) );
writer.write( " cfA" );
writer.write( jobNumber );
writer.write( localHostName );
writer.write( (int)'\n' );
writer.flush();
if ( in.read() != 0 )
{
throw new PrinterException( "LPD print server '" + hostname + "' refused print job '" + documentName + '\'' );
}
writer.write( controlFile.toString() );
writer.write( 0 );
writer.flush();
if ( in.read() != 0 )
{
throw new PrinterException( "LPD print server '" + hostname + "' refused print job '" + documentName + "' control file" );
}
// Send print file
writer.write( 0x03 );
writer.write( String.valueOf( documentData.length ) );
writer.write( " dfA" );
writer.write( jobNumber );
writer.write( localHostName );
writer.write( (int)'\n' );
writer.flush();
if ( in.read() != 0 )
{
throw new PrinterException( "LPD print server '" + hostname + "' refused print job '" + documentName + "' document header" );
}
out.write( documentData );
out.write( 0 );
out.flush();
if ( in.read() != 0 )
{
throw new PrinterException( "LPD print server '" + hostname + "' refused print job '" + documentName + "' document data" );
}
}
finally
{
try
{
socket.close();
}
catch ( final IOException ignored )
{
}
}
}
catch ( final IOException e )
{
throw new PrinterIOException( e );
}
}
/**
* Connects to the LPD print server. This method will retry a few times if
* needed, because some printers occasionally refuse incoming connections.
*
* @return Connected socket.
*
* @throws IOException if an I/O error occurs.
*/
private Socket connect()
throws IOException
{
Socket result = null;
int attempts = 3;
while ( attempts > 0 )
{
try
{
result = new Socket( _hostname, _networkPort );
break;
}
catch ( final ConnectException e )
{
if ( --attempts == 0 )
{
throw e;
}
try
{
Thread.sleep( 10L );
}
catch ( final InterruptedException ignored )
{
Thread.currentThread().interrupt();
break;
}
}
}
if ( result == null )
{
throw new AssertionError();
}
return result;
}
}
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